Micro:bit — BBC Gets A Million Kids Into Embedded Dev
In the Early 1980s, the BBC launched a project to teach computer literacy to a generation of British schoolchildren. This project resulted in the BBC Micro, a very capable home computer that showed a generation exactly what a computer could do. These children then went home, turned on their ZX Spectrums, and became a generation of software engineers. Still, the BBC Micro is remembered fondly.
The computer revolution is long over, but today we suffer a sea change of embedded processors and microcontrollers. With Arduinos and Raspberry Pis, the BBC has decided it’s time to put the power of an …read more
Logic Noise: Ping-pong Stereo, Mixers, and More
So far on Logic Noise, we’ve built up a bunch of sound-making voices and played around with sequencing them. The few times that we’ve combined voices together, we’ve done so using the simplest possible passive mixer — a bunch of resistors. And while that can work, we’ve mostly just gotten lucky. In this session, we’ll take our system’s output a little bit more seriously and build up an active mixer and simple stereo headphone driver circuit.
For this, we’ll need some kind of amplification, and our old friend, the 4069UB, will be doing all of the heavy lifting. Honestly, this …read more
Gates to FPGAs: TTL Electrical Properties
On the path to exploring complex logic, let’s discuss the electrical properties that digital logic signals are comprised of. While there are many types of digital signals, here we are talking about the more common voltage based single-ended signals and not the dual-conductor based differential signals.
I think of most logic as being in one of two major divisions as far as the technology used for today’s logic: Bipolar and CMOS. Bipolar is characterized by use of (non-insulated gate) transistors and most often associated with Transistor Transistor Logic (TTL) based logic levels. As CMOS technology came of age and got …read more
True Random Number Generator for a True Hacker
How can you generate random bits? Some people think it’s not easy, others will tell you that it’s pretty damn hard, and then there are those who wonder if it is possible at all. Of course, it is easy to create a very long pseudorandom sequence in software, but even the best PRNG (Pseudorandom Number Generator) needs a good random seed, as we don’t want to get the same sequence each time we switch on the unit, do we? That’s why we need a TRNG (True Random Number Generator), but that requires special hardware.
Some high-end microprocessors are equipped with …read more
Talking Big Changes At SparkFun With Nathan Seidle
SparkFun, you know them, you love them. They list themselves as “an online retail store” but I remember them for well-designed breakout boards, free-day, videos about building electronics, and the Autonomous Vehicle Competition. This week SparkFun turned my head for a different reason with the announcement that [Nathan Siedle], founder and CEO will be stepping down. He’s not leaving, but returning to the Engineering department while someone else takes the reigns. I spoke with him yesterday about what this means for him, the company, and what SparkFun has planned for the future.
Stepping Down Without Saying Goodbye
[Nate] founded Sparkfun …read more